import sys
import copy

IP_TAB = [58,50,42,34,26,18,10,2,
        60,52,44,36,28,20,12,4,
        62,54,46,38,30,22,14,6,
        64,56,48,40,32,24,16,8,
        57,49,41,33,25,17,9,1,
        59,51,43,35,27,19,11,3,
        61,53,45,37,29,21,13,5,
        63,55,47,39,31,23,15,7]

IP_1_TAB = [40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,
        38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,
        36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,
        34,2,42,10,50,18,58,26,33,1,41, 9,49,17,57,25]

Ext_TAB = [32, 1, 2, 3, 4, 5, 4, 5, 6, 7, 8, 9, 8, 9, 10,11,
        12,13,12,13,14,15,16,17,16,17,18,19,20,21,20,21,
        22,23,24,25,24,25,26,27,28,29,28,29,30,31,32, 1]

P_TAB = [16,7,20,21,29,12,28,17, 1,15,23,26, 5,18,31,10,
        2,8,24,14,32,27, 3, 9,19,13,30, 6,22,11, 4,25]

S1_TAB = [14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7,
        0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8,
        4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0,
        15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13]

S2_TAB = [15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10,
        3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5,
        0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15,
        13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9]

S3_TAB = [10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,
        13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,
        13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,
        1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12]

S4_TAB = [7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15,
        13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9,
        10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4,
        3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14]

S5_TAB = [2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9,
        14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6,
        4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14,
        11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3]

S6_TAB = [12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11,
        10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8,
        9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6,
        4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13]

S7_TAB = [4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1,
        13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6,
        1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2,
        6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12]

S8_TAB = [13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7,
        1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2,
        7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8,
        2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11]

S_TAB = [S1_TAB,S2_TAB,S3_TAB,S4_TAB,S5_TAB,S6_TAB,S7_TAB,S8_TAB]

PC_1_TAB_1 = [57,49,41,33,25,17,9,
        1,58,50,42,34,26,18,
        10,2,59,51,43,35,27,
        19,11,3,60,50,44,36]

PC_1_TAB_2 = [63,55,47,39,31,23,15,
        7,62,54,46,38,30,22,
        14,6,61,53,45,37,29,
        21,13,5,28,20,12,4]

PC_2_TAB = [14,17,11,24,1,5,3,28,
        15,6,21,10,23,19,12,4,
        26,8,16,7,27,20,13,2,
        41,52,31,37,47,55,30,40,
        51,45,33,48,44,49,39,56,
        34,53,46,42,50,36,29,32]

bit_shifts = [1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1]

def change_PC_1():
    for i in xrange(len(PC_1_TAB_1)):
        a = PC_1_TAB_1[i] / 8
        PC_1_TAB_1[i] -= a
    for i in xrange(len(PC_1_TAB_2)):
        a = PC_1_TAB_2[i] / 8
        PC_1_TAB_2[i] -= a

def generate_key(key):
    for i in xrange(7,-1,-1):
        key.pop(i * 8 + 8)
    return key

def process_key_56(key,shift):
    left = key[1:29]
    right = key[29:57]
    for i in xrange(shift):
        temp1 = left.pop(0)
        left.append(temp1)
        temp2 = right.pop(0)
        right.append(temp2)

    temp1 = copy.deepcopy(left)
    temp2 = copy.deepcopy(right)
    temp_left = []
    temp_right = []
    for i in PC_1_TAB_1:
        temp_left.append(key[i])
    for i in PC_1_TAB_2:
        temp_right.append(key[i])
    temp_left.extend(temp_right)#merge the left and right part
    res = []
    for i in PC_2_TAB:
        res.append(temp_left[i-1])
    temp1.extend(temp2)
    temp1.insert(0,'a')
    return res,temp1

def revert_four(dig):
    temp = []
    for i in dig:
        for j in [8,4,2,1]:
            temp.append(i/j)
            i %= j
    return temp

def round_i(left,right,key):
    left_res = right
    right_temp = []
    four_dig = []
    for i in Ext_TAB:
        right_temp.append(right[i-1])
    for i in xrange(len(right_temp)):
        right_temp[i] ^= key[i]
    for i in xrange(len(S_TAB)):
        row = right_temp[i * 6 ] * 2 + right_temp[i*6 + 5]
        col = right_temp[i*6 + 1] * 8 + right_temp[i*6 + 2] *4 + right_temp[i*6+3] * 2 + right_temp[i*6+4]
        four_dig.append(S_TAB[i][row*16+col])
    four_dig = revert_four(four_dig)
    four_dig_temp = []
    for i in P_TAB:
        four_dig_temp.append(four_dig[i-1])
    for i in xrange(len(left)):
        left[i] ^= four_dig_temp[i]
    return left_res,left
        
def gen_input():
    a = sys.argv[2]
    if not len(a) == 64:
        print "input a 64 bit binary"
        exit();
    temp = [int(i) for i in a]
    return temp[0:32],temp[32:64]

def code_or():
    shell_name, method, key, data = sys.argv
    if not len(data) == 64:
        print "key must be a 64 bit binary"
        exit()
    if not len(key) == 64:
        print "key must be a 64 bit string"
        exit()
    temp = [int(i) for i in data]
    left = temp[0:32]
    right = temp[32:64]
    print key
    key = '0'+key
    x = [int(i) for i in key]
    x = generate_key(x)
    keys = []
    if method == "e":
        for i in xrange(16):
            res, x = process_key_56(x,bit_shifts[i])
            keys.append(res)
            left,right = round_i(left,right,res)
        left.extend(right)
        for i in xrange(len(left)):
            left[i] = str(left[i])
        print ''.join(left),
    elif method == "d":
        for i in xrange(16):
            res, x = process_key_56(x,bit_shifts[i])
            keys.append(res)
        for i in xrange(len(keys),0,-1):
            right,left = round_i(right,left,keys[i-1])
        left.extend(right)
        for i in xrange(len(left)):
            left[i] = str(left[i])
        print ''.join(left),
    else:
        print "error!"
        exit()


if __name__ == "__main__":
    change_PC_1() #modify the PC_1_TAB
    code_or()
